As a conventional device for judging a degree of arteriosclerosis, Japanese Patent Laying-Open No. 2000-316821 (hereinafter referred to as Patent Document 1), for example, discloses a device for judging a degree of arteriosclerosis by checking a velocity that a pulse wave ejected from the heart propagates (hereinafter referred to as PWV: pulse wave velocity). Since the pulse wave velocity increases as arteriosclerosis progresses, PWV serves as an index for judging a degree of arteriosclerosis. By applying cuffs or the like for measuring pulse waves to at least two locations, such as an upper arm and a lower extremity, and measuring pulse waves simultaneously, PWV is calculated from the difference between time points at which the respective pulse waves appear and from the length of an artery between the two locations to which the cuffs or the like for measuring pulse waves are applied. PWV differs in value according to measurement sites. A typical PWV includes baPWV in the case where measurement sites are an upper arm and an ankle, and cfPWV in the case where measurement sites are the carotid artery and the iliac artery.
As a technique for judging a degree of arteriosclerosis from an upper arm's pulse wave, Japanese Patent Laying-Open No. 2007-44362 (hereinafter referred to as Patent Document 2) discloses a technique for providing a double structure including a blood-pressure measuring cuff and a pulse-wave measuring cuff.
Japanese Patent Laying-Open No. 2004-113593 (hereinafter referred to as Patent Document 3) discloses a technique for separating an ejected pulse wave ejected from the heart and reflected waves from the branch of the iliac artery and a hardened portion in an artery, to thereby judge a degree of arteriosclerosis based on the difference and ratio between their amplitudes, the difference between time points of appearance, and the like.    Patent Document 1: Japanese Patent Laying-Open No. 2000-316821    Patent Document 2: Japanese Patent Laying-Open No. 2007-44362    Patent Document 3: Japanese Patent Laying-Open No. 2004-113593    Patent Document 4: Japanese Patent Laying-Open No. 2005-230175